Vapor electric apparatus.



C. BRADWAY. VAPOR ELECTRIC APPARATUS.

APPLICATION FILED APR. 4, 1904.

925,620. Patented June 22,1909.

Witnesses: Inventor" g Ch attin Bradway;

names snares rarest current- OHATTIN BRADWAY, OF SOHENEOTADY, NEW YORK,ASSIGNOR TO GENERAL ELECTRIC COMPANY, A CORPORATION OF NEW YORK.

No. eaaeao Specification of Letters Patent.

varon nLncrnrc nrrnna'rns.

Patented June 22, 1909.

Application. filed April 4, 1904. Serial No. 201,477.

To all whom it may concern:

Be it known that I, CHATTIN BRADWAY, a citizen of the United States,residing at Schenectady, and State of New York, have invented certainnew and useful Improvements in Vapor Electric Apparatus, of which thefollowing is a specification.

My invention relates to improvements con cerning apparatus of that typein which an electric discharge is produced between electrodes in theexhausted chamber, which contains a vaporous or gaseous matter derivedfrom at least one of the electrodes, and it consists more particularlyof automatic means entirely contained within the exhausted chamber forstarting the apparatus into operation. v

The featureswhich I regard as characterizing the novelty of my inventionare set forth in the appended claims, which are to be construed in viewof the following description of the invention, and which, together withthe accompanying drawing, illustrates one of its embodiments.

The invention provides means operating automatically whereby theapparatus upon supply of current, will start 1nto operation.

I employ in the presence of vapor, a conducting medium for current, inwhich a gap may be interposed whereby an electrical discharge will beproduced. The means for creating v such gap constitutes the invention,and it rests for its basis upon the principle that a conductor will,when conveying current, expand under the heating effect of the current,and the change of dimension of the conductor or its expansion isutilized for breakin the circuit and thereby causing an initial electricdischarge for starting the apparatus.

In practically embodying my invention I have elected to illustrate it asan electric lamp of the mercury arc type, of which, referring to thedrawing, 1 is an exhausted chamber of glass comprising a tube 2-, ofindefinite length, as indicated by broken lines, and crowned by abulbous enlargement or vapor-condensing chamber 3. Inthe lower end ofthe tube 2 is contained an electrode 4, preferably of mercury, the vaporof which ills the chamber and forms the medium for in the county ofSchenectadyconverting electrical ener y into light, and at the upper endof the tube, below the condensing chamber, is supported in fixedposition an electrode 5, said electrodes being electrically connected tolead-in wires 6 and 7, respectively, which extend through the wall ofthe chamber and convey current from a suitable source by means of themains 8 and 9. Such is a known type of mercury vapor lamp, and inapplying my invention thereto an auxiliary circuit is provided in theexhausted inclosure or chamber, which contains the starting deviceemployed for creating the auxiliary electric discharge for producing themain discharge between the electrodes 4 and 5/ The starting meansconsists of an expansible member that is connected in circuit with themains and is arranged in such cooperative relation to the other portionof the circuit that when current causes the member to expand, due to theheat resulting from the partial conversion of the energy passing throughthe member into heat, the circuit will be broken and an arc sprungacross the gpp thus formed. I have found that the coe icient ofexpansion of carbon or similar refractory material, in the form of afilament or rod, renders such material available for use as theexpansible member, when provided in suitable length, whereby thecumulative expansion is adequate to give the necessary range of movementto enable a gap to be formed, as already pointed out. One end of thefilament or red is fixed while the free end is provided with a suitablecontrivance which normally dips into the mercury electrode and isadapted to be withdrawn by the expansion of the filament or rod underthe int uence of current. As shown inthe drawing, the carbon filamentor'rod 10 is substantially co-extensive with the length of the tube,terminating at its lower end a short distance above the lower electrodeor body of mercury 4, but the exact length of the filamentis notarbitrary. Its upper end is anchored at the wall of the chamber and isconnected with the conductor 11, and at its lower end the filament issuspended to exand freely inthe direction. of its length.

nt ermediate the filament and the mercurial a which the auxiliaelectrode, and movably attached to the depending end of the filament, isa carbontipped tilting lever 12, of iron or other nonvaporizablesubstance, which is slightly immersed at its tip in the body of mercury.This is the normal position of the lever in circuit, composed of theconductor 11, thefi ament 10 with the lever 12 and the main electrode 4,is completed. The

lever is pivoted, as a first-class lever, on a supporting lug 13extending from the wall of chamber between the main electrode, startingthe lamp into full 0 eration.

In order to render the filament idle, as a conductor of current, duringthe main operation of the lamp, a cut-out apparatus 15 may be providedwhich is located in circuit with the main 9. This apparatus consists ofa solenoid 16 which, when energized, acts upon a core 17 carrying abridging contact 18 which connects the contact points 19 and 20 in theauxiliary circuit. Upon a flow of current incident to the main dischargeand resulting from the current passing through the ionized vapor of thelamp to the anode 5, the solenoid will be energized and will operate thecut-out apparatus. The main current thus passing through the solenoidretains the cutout apparatus open during the continued operation of thelamp, and as soon as the current in the main circuit is interrupted forany reason, the solenoidis immediately deener gized and the cut-outapparatus restored, thereby placing the auxiliary circuit again incondition of initial operation.

In accordance with the provisions of the patent statutes, I havedescribed the principle of operation of my invention, together with theapparatus which I now consider to represent the best embodiment thereof;

but I desire to have it understood that the apparatus shown 'is onlyillustrative, and that the -1nvent1on can be carried out by other means.

Vfhat I claim as new and desire to secure I by Letters Patent of theUnited States, is,

1. In a vapor electric apparatus, the combination of a vapor containingchamber, an

electrode therein, and nea'ns 'foropcning the circuit within said.chamber, said means com-- prising an cxpansiblc clement changeable inWith ' length due to the heat effect of currenli passed therethrough,said ex ansible element eing initially in circuit wit said electrode. 2.In a vapor electric a 'pa'ratus, the combination of an exhausted camber, electrodes therein one at least of which is va orizable, and anauxiliary starting circuit inc uding an arc-producing device which islocated within the chamber and operates by expansion when heated withcurrent.

bination of an inclosure, electrodes therein one of which isvaporizable, and a conducting medium in the inclosure normall in contactwith the vaporizable electrode w ich contact is broken by the ex ansionof the medium under the influence'oi heat due to the passage ofcurrerit.

' 4. In a vapor electric apparatus, the combination of an inclosure,electrodes therefor, andfa filament electrically connected at one endwith one electrode, which connection is adapted to be broken b theexpansion of the filament under the in uenceof heat arising from thepassage of current therethrough.

5. In a vapor electric apparatus, the combination of an inclosure,a-vaporizable electrode at one end thereof a non-vaporizable electrodeat the other end of the-inclosure, and a conductor extending throu h theinclowhich is partially immersed in the va orizfrom the said electrodeby the expansion of the other member.

bination of an inclosure, a va orizable electrode at one 'end,'anelectro e cooperating therewith at the other end, a filament suspendedin the inclosure, which is adapted to exp and when conveying current, alever connected at the lower end of the filament and supported incontact with the vaporizable electrode; and means supplying current tothe filament and electrodes.

7. In a vapor electric apparatus, the combination of an exhaustedchamber, a va 0- rizable electrode at the lower end thereo anon-vaporizable electrode at the upper end, supply mainsjconnecte'd withthe e ectrodes, means initial]: connected with the lower electrode, an eectric discharge producing device included in said means which iscontrolled by the thermal efiect of current therein, and a cut-outapparatus for controlling the supply of current to the means.

8. In a vapor electric a paratus, the combination of an exhausted camber, main elec- 1 convoy current initially to a main electro e, said,auxiliary olectrbde comprlsing a filament of refractory material and amovable 3. In a vapor electric apparatus, the com sure and composedoftwo mem ers, one of able electrode and adapted to be with rawn 6. In avapor electric apparatus, the com trodes, an auxiliary electrode adaptedto member connected therewith which is withdrawn from the main electrodeto produce an a conductor initially supplied with current 10 electricdischarge when the filament is caused and expansible to produce movementof said to expand by the efiect of current passing contact member.through the same, and Ifiains for supplying In witness whereof, I havehereunto set my 5 current to the electrodes. hand. this 2nd day ofApril,1904.

9. The combination of an evacuated v OHATTIN BRADWAY. chamber,electrodes therein, and are produc- Witnesses: ing means within saidchamber comprising a BENJAMIN B. HULL, movable contact membercooperating with HELEN ORFoRD.

